BE would handle this and you should look at optimized deduplication with CASO. HOWEVER...don't go BE 2012 yet as the Beta that is no unfortunately pushed out till end of May 2013 is going to fix a lot of issues with product support and the issues that plagued its release.

Best ask the same questions in the NBU forum...

However...

4. Yes it can do this, but BE 2012 became server-centric, not resource-centric. Each server has its own job. If you have a virtual environment, then maybe BE 2012 V-Ray is the way to go for ease of licensing etc.

6. There should be no hassle with this. If I remember correctly, it's 1.5GB RAM for every 1TB you dedupe. More RAM and multiple cores on the CPUs will ensure you have the grunt to get the jobs done. Your WAN link must also be fast enough to get the data across.